Coral reef monitoring in St Maarten 2016 and 2017 Impact of Hurricane Irma on St Maarten Reefs and on the Man of War Shoal Marine Protected Area
Carnivorous fish biomass, with a focus on grouper and snapper biomass, varied the most amongst these reefs after the hurricanes. These carnivores increased in biomass and changed reef location, shifting from reefs outside of the Marine Park to those within. Mechanical damage and sediment shifting, both depositing and removal, were observed on the reefs. Coral cover for St Maarten decreased from 6.13% to 3.74% after the passage of Hurricanes Irma and Maria. The mean percentage cover of macroalgae, sponges and crustose coralline algae (CCA) increased. The Macroalgal (MA) Index (a function of the mean percentage cover and height that determines macroalgal biomass) did not vary at country level. Coral recruit density increased after the hurricanes, but at similar levels in both monitoring zones. Reef health improved with a reduction of bleached coral cover.